RE: [RFT][PATCH v7.3 5/8] cpuidle: Return nohz hint from cpuidle_select()

From: Doug Smythies
Date: Thu Mar 22 2018 - 16:47:01 EST


On 2018.03.22 10:40 Rafael J. Wysocki wrote:

...[snip]...

>The difference between this and the original v7 (of patch [5/8]) is
> what happens in menu_update(). This time next_timer_us is checked
> properly and if that is above the tick boundary and a tick wakeup occurs,
> the function simply sets mesured_us to a large constant and uses that to
> update both the correction factor and data->intervals[] (the particular
> value used in this patch was found through a bit of experimentation).
>
> Let's see how this works for Thomas and Doug.

System idle test done for 74 minutes.
After boot and after the system settles down for a couple of minutes,
Processor package power is constant at 3.7 Watts. (great)
Not worth a new graph to show a flat line.

V7.3 average package power = 3.68 Watts.
V7 average package power = 3.68 Watts
V7.2+ average package power = 4.06 Watts (+10%)

> For easier testing there is a git branch containing this patch (and the
> rest of the series) at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git \
> idle-loop-v7.3

Thanks. I used this git branch this time and for the first time.
Much easier.

... Doug